Dean,

I'll try to write something up over the next week or so. Honestly, I'm very particular about my battery bank since it wasn't cheap and I only get nervous when it goes below 25% state of charge. All the literature tells me that even at 20% SOC, you're going to get 2000 cycles out of your batteries, but my concern is that the reported SOC is a bit of an average. Each battery has 4 cells and I have 6 batteries, so if one of those 24 cells drops below 2.5v or so, it could damage that cell and hence the 4-cell battery irreversibly. The SOC number doesn't reflect individual cell voltages, only the bank as a whole.

Of course I have a BMS that monitors individual cells, but given the way an Amel is wired, even that solution isn't perfect. I will expand on that in my longer post explaining my system and the challenges I faced. But for me, to be safe, I start up the genset if the bank drops below 25%. 

I am considering adding an automatic trigger to start the genset at 25% state of charge and stop the genset at 75% SOC. But that presents other problems, so I'm hesitating. 

--
Scott 
2007 A54 #69
SV Tengah
www.svtengah.com